Markdown Here appears to be unmaintained and is certainly incompatible with Thunderbird 68.0. I have not been able to raise the developer of it at all and PRs a

Markdown Here appears to be unmaintained and is certainly incompatible with Thunderbird 68.0. I have not been able to raise the developer of it at all and PRs are not being merged. https://github.com/adam-p/markdown-here/issues/577 https://github.com/adam-p/markdown-here/issues/577